Fiber optic communication systems are becoming prevalent in part because service providers want to deliver high bandwidth communication capabilities (e.g., data and voice) to customers. Fiber optic communication systems employ a network of fiber optic cables to transmit large volumes of data and voice signals over relatively long distances. Optical fiber connectors are an important part of most fiber optic communication systems. Fiber optic connectors allow two optical fibers to be quickly optically connected without requiring a splice. Fiber optic connectors can be used to optically interconnect two lengths of optical fiber. Fiber optic connectors can also be used to interconnect lengths of optical fiber to passive and active equipment.
A typical fiber optic connector includes a ferrule assembly supported at a distal end of a connector housing. A spring is used to bias the ferrule assembly in a distal direction relative to the connector housing. The ferrule functions to support an end portion of at least one optical fiber (in the case of a multi-fiber ferrule, the ends of multiple fibers are supported). The ferrule has a distal end face at which a polished end of the optical fiber is located. When two fiber optic connectors are interconnected, the distal end faces of the ferrules abut one another and the ferrules are forced proximally relative to their respective connector housings against the bias of their respective springs. With the fiber optic connectors connected, their respective optical fibers are coaxially aligned such that the end faces of the optical fibers directly oppose one another. In this way, an optical signal can be transmitted from optical fiber to optical fiber through the aligned end faces of the optical fibers. The fibers in a multi-fiber ferrule must all be brought into contact. Preferably, the tips of the fibers should all lie in a line (for a single row of fibers) or plane (multiple rows of fibers).
Polishing results in a nearly planar surface; however this surface is not consistently oriented with respect to the axis defined by the guide pins. For example, the fiber slope angle, which is nominally zero, is not well controlled. It is difficult to measure this angle accurately, since it involves features that extend in three dimensions: the axes of the alignment pin passageways extend along a longitudinal axis, and the contact face of the ferrule extends along major (or lateral) and minor (or vertical) axes. The pins are held very rigidly by the ferrules, such that the ferrules cannot rotate about the minor axis to allow the ends of the fibers to come into contact when the ferrules are urged forward by a spring force.
Alignment connection systems have been developed to improve the loss of physical contact between fiber-optic connectors. However, there is a need to reduce the rotational stiffness of the ferrule and guide pin mechanical system such that physical contact can be made between all fibers in a multi-fiber connector.